Posted
by
michael
on Friday July 04, 2003 @08:08AM
from the umbrella-jousting dept.

Anonymous Award writes "Remember those old Isaac Asimov tales of cities of the future, where everybody walked along on moving sidewalks, sometimes clear across a country? Today's airport travelators have always been disappointingly pale imitations of these, but now in
Paris we may be seeing the
true birth of this wonderfully dangerous mode of mass transportation. Its
already as fast as a bus, but when they can crank them up to motorway speeds...
well, lets just say this may have a better chance of having cities designed
around it than certain other recent innovations."

When it gets up to a certain speed, the wind resistance against your body will be greater than the friction of the belt against your feet, and you will cease to move forward...

Now this should look funny. But if you enclose the belt in a tube, with air moving with the speed of the belt (either artificially propelled or just "pulled" by the belt), the wind resistance becomes less of a problem.

All the people on the belt should pull enough air along with them so air pumps wont be that necessary.

A basic invention is not dissimilar to a train - you get into a box that has rollers/wheels on the bottom. Internal friction in the wheels/rollers will accelerate the box on the conveyor belt and the box can then be accelerated to whatever speed wanted (extremely fast if in a vacuum). The same effect will slow the box down when it comes off the other end.

Boxes can then be sent back using a travellator that goes the other way, or another idea is to make them collapsible so they can go back under the conveyorbelt.

unless it is contained in a tunnel with the wind being blown behind you at the same speed. Oops, the conveyor belt stops, blown onto your face, sue! Oops, wind stops, blown backwards, smash the face of the person behind you, sue! You will have people literally running into the back of you.

"Once the wind resistance equals the force from the belt against your feet, you will cease to accellerate, it's not like you're suddenly going to stop."

This isn't a case of two opposing forces acting at the center of gravity of a rigid body. You've got the friction force of the belt acting tangentially at the very bottom, and the drag force acting in the opposite direction all over the body. What would actually happen when the drag force got too strong is that the high torque would cause some people on

When it gets up to a certain speed, the wind resistance against your body will be greater than the friction of the belt against your feet, and you will cease to move forward...

IANAP either, BUT I just walked to our wind tunnel at university [rau.ac.za], and stood in it. It takes no effort to stay upright up to 50km/h. At 80km/h one has to concentrate on staying upright, didn't go faster than that.

Well actually the friction only acts on your feet, while the wind resistance acts on your whole body (the front of it anyway), so you'll very likely fall backwards rather than just stop moving forward...

What I remember of the story was that they had this rolling road that spanned the USA from east to west, with lanes that went faster and faster. You got on the first slow speed lane, and just walked over to successively faster lanes. The fastest lane was some cool 1950's velocity like 150-300mph.

Some disgruntled workers clipped a lane or two, with expected results.

Nice to see Robert Heinlein's idea making it to reality, now if I could only speak Basic with someone on the moon, or have a farm on Ganymede!

of course, in the story the attack takes place by having the men travel via a self balancing unicycle - segway is well on its way to that view.
I suspect that we will see cities using both ideas in the future.

2 layers. Top layer runs in a circle. The bottom layer looks like our conveyor with hooks to catch the top layer and pull it. It would have to have the capaibility of being pulled back to allow the upper belt to slide incase the conveyor stops.

As mentioned in the article, the most difficult issue is the transition from moving on the walkway and moving on stationary ground.

It seems to me the best solution to this is to have "lanes" in the walkway. The far left lane would move at the maximum speed, whereas successive lanes to the right would be decelerated. When exits were reached, you could easily step to the right to get to a lower speed; the transition between 9km/h and 6km/h is still a transition, but its less than 9km/h to 0km/h.

I dont know; in my personal experience with these devices (in their slower, American and Australian forms), I've rarely seen people hold the railing. Most often, they're holding their bags, walking, or reading, etc.

Obviously, I'm not suggesting no one uses the railing. But the people who need the railing (i.e. the elderly, the poorly balanced) might not be well advised to use such a device as this.

Alternately: put hanging handles a la the subway system. They'd be adjustable (i.e. you could raise/lower them) with one hand, and then you'd avoid the need for a railing.

You need to make sure that, whatever you do, you jam both of them at once if one of them jams.

It seems stupid that someone jamming the handles should jam the walkway, but once I was going down an escalator, casually leaning on the rail to look at some store, and some idiotic kids at the top of the escalator stuck something in the railing (whcih for some reason was partially open) and made the handhold jump track. So suddenly I was leaning on something that had stopped moving...and my feet kept going, and I

The problem would be where would the poles *go* when you reached the end of the strip. If they just went around like on a conveyor belt, someone would get themselves pinned between the pole and the floor either out of malice (if it didn't slice through the person, the belt would jam or break) or sheer stupidity.

If the belt ran around a deeper area, I could see an "internal" belt, carefully timed and placed so that the poles sank down at the end of the track, where the internal belt just held the poles and the external one had holes for the poles to stick through.

>>It seems to me the best solution to this is to have "lanes" in the walkway.

In fact, this is exactly what they have in Paris. The high-speed travelator was put in between two other standard moving walkways. One of the standard walkways goes in the opposite direction, and the other lets you move along at 3km/h. So pedestrians do have a choice between the 9km/h lane, the 3km/h lane, or the "old fashioned" 0km/h walkway.

The only thing I don't like about the highspeed walkway is the fact that it is only running during the workday, Mon-Fri. There were enough people who were falling on it that they had to employ people to stand at both ends of the thing to make sure that users don't hurt themselves...

Not quite. The idea would be to have the lanes running at different speed alongside each other (without handrails in between and no gaps) and be able to SWITCH lanes to speed up. This was the system that Heinlein laid out in The Roads Must Roll. The system for accelerating used looks like a clever solution, though. I'm not sure how practical it would be to switch lanes in reality.

Well, if the existing travelator were to become the "slow lane" in a Heinlein Road, that would still work. The initial accelerating lead-in would get you up to 9Km/h, then stroll sideways to a faster strip.

An easier way to do this woul be to do what they've done recently in Japan to solve this issue. They've got sliding panels as the tread that propels you. Toward the beginning and the end, the panels slide over each other, which slows down the railway. This is because each section of the railway lets a certain number of these sliding panels through per minute, but as they panels lap over each other, the speed needed to let the same number of panels through decreases. This is probably tricky to visualize.

In the middle of the runway, the panels look like this (different numbers to indicate the different individual panels)

(sorry about the multiple _s...I've never had to try and find an alternative for on/. before)
At the ends, they slide together like this:

111111111112222222222233333333333
222222222223333333333344444444444

So that even though the speed slows down, the panels don't squish each other, breaking the machine. I saw it on TV, and the dude was just whipping along the corridor. If they combined this system at a higher pace with the roller system they've got in France, they could probably take the speed up a fair bit.

It seems to me that a better solution would be to have rotating disks at transistion points along the route. This way people could step onto the outer edge of the disk (where the outer angular velocity equals the linear velocity of the belt). They could walk into the center (where the angular velocity is much lower) and then step off into the center hole.

Of course, the problem with this is that the disk would need to be enormously large to make the centripetal force reasonable.

I read this this morning on the BBC and immediately booked a weekend in Paris for myself and my beloved - hey its summer, the flights were under 200 sterling return and I cant wait to see her fall on her arse as we get on this thing!

I'm just hoping they dont stop you taking skateboards onto this thing!

It's unlikely you'll ever reach motoway speeds: wind resistance against a moving person at that speed will cause lots of problems (translation: you'll be on your butt somewhere around 40km/h). Also, it should be noted that the "bus speed" they list in the article is 9km/h. That's not exactly speedy by open road standards, but is probably pretty fast by congested downtown standards.

Better yet, let's put in seats for people to sit on. And then we could put groups of seats together on a fixed platform. At that point you don't need all the surface area, so you can propel the platforms from the edges.

Here's the really cool (and tricky) part: then you put the motors inside the platforms themselves. Then you don't need miles long rubber belts that can wear out. Just replace them with concrete floors. And to keep people from falling out, add walls. If you add a roof, you can operate them outside, even when it's raining! And for more capacity (to make up for having the seats in the first place), you can use more than one platform stacked together.

About wind resistance: you could construct a tube around the travelator and then blow wind through it at the speed of the trottoir. Yeah, that might work.

But think about the possibilities for gruesome injuries! Naa, this whole travelator concept only goes so far...

I think I'll wait for my magnetic/antigrav boots, undulating floors, or at least small transportation capsules that go around through pipes. Maybe we should just redesign cities to accomodate more people more elegantly, that would be a start!

The operative word was "fast". Walking speed is 5-6 km/h tops. In a crowded area such as a train station carrying luggage probably closer to 3-4 km/h. The current high speed travelators go at 9, and you can walk on them for a total of something like 12-15 km/h, a significant increase.

Well, have you ever been in a public space with a large group of people? As simple as the concept is, many people can't seem to understand that there is a reason people go to airports, etc... they are trying to get somewhere! However, throw in a few shutter-bugs taking pictures of everything, or social butterflies that have to stop and talk to every third person they see, and you've got one large fleshy traffic jam. If I could bypass all of the slow, stupid and otherwise unm

I went Paris for the weekend in March and we went through Montparnasse one day and went on this travelator.

They have guys watching to stop certain people getting on, I have heard they have had to pay out for injuries to some people.

First it accelerates you to 9kph then it is exactly like a normal travelator only much faster.

I loved it.

The only problems are the acceleration and deceleration phases. It's very bumpy. You have to hold on to the rail. If they can fix those aspects these things will start appearing in airports everywhere.

How are the acceleration and deceleration phases done technically? Since it's a conveyor belt, they can't just slow down the whole thing once you move towards the end (as it would slow everybody down).

I see two possibilities:1. At the end of the 9kph belt, there is a 6kph, and then a 3kph belt, and people have to jump from belt to belt2. The platforms that everybody stands on are collapsible: To speed up, they grow longer, and to speed down, the become shorter again.

The accel/decel zones are like a number of ballbearings or something, which are rotating at gradually increasing speeds. This is why you need to keep both feet on the ground, because otherwise you could end up falling over.

It would seem to me that the sheer number of moving parts in a kilometre or so of walkway must make the chances of frequent failures pretty high compared to other public transport methods. How fault-tolerant is it? Any French Slashdotters able to answer?

it's a poor solution.. better would be organic, something like stomach cillia, where the floor doesn't move the length of the journey, but little tiny bits from in place do- not my idea, something I read once.

the individual elements take turns dropping, moving a tiny bit, pushing up again, and moving you a tiny bit... done repeatedly= ya move down the floor- which doesn't move.

less to break down, and spilled drinks and food (as long as they aren't too hot) are actually welcome...

...And it's located in the tunnels beneath the Geneve airport. They've got a system like this there, but I'm not sure they run it at the same speed. At least I didn't think it was moving that fast when I used it. Quite fun, atually.I also use a similar thing in a local supermarket. All you'd have to do is crank up the speed on it to equal the Paris one, but then again, it's slighly elevated and I don't think people like being catapulted from the 2nd floor...

I was at Toronto International airport last year and saw an Ethiopian woman and young child at the top of an escalator. They were clearly having problems. I took the hand of the child and helped her take "the big step". Presumably her first. She had no problems. Then I realised that I was helping the wrong person. The mother was now stranded at the top wondering what to do.

Teavelators, escalators, revolving doors, they seem natural and intuitive to those who are used to them.

As an idea, these expressways are a fairly good way of transporting humans. They travel at constant speed, so there should be no obvious difference to the traveller, no matter what the speed is. Of course, in reailty we'd experience air resistence; try sticking your head out of the window on a car going at 70mph. but there may be some way of reducing this in enclosed tunnels, like blowing air at the same velocity as the floor is moving.

In Asimov's vision (I think), the different-speed strips were parallel to each other, not serial like this French version. This meant that you's step to the side to go onto a faster strip, and keep going until you hit the fastest one, which could be several hundred miles an hour. As the differential in speed between the strip you are on and those near is never more than about 1mph, you won't do yourself any serious damage by falling over. see diagram:

---->---7mph->--
---->---8mph->--
---->---9mph->--
etc.

This structure makes them easier to 'network'. The only danger, I suppose, is if a strip breaks then the speed-differential between it and then next one could be massive.

I suppose any serious implementation would use some kind of semiconductor thang to decrease friction, and on a wide scale could be very energy efficient. These things are probably more useful to society than a Segway, but you'd have to design a city around them from the ground up, so I doubt they'll change the way we live just yet.

R. A. Heinlein, _The Roads Must Roll_And it was a 5 MPH difference between lanes. Every lane has to have separate motors, etc, so you don't want too many of them. 5 MPH is a brisk walk so it's not hard to move from one to the next.

When I first read "already as fast as a bus" I envisioned this thing cranking along at 30mph, people hanging on for dear life with the wind blowing their hair back. 9 km/h is a decent jogging pace, so maybe they are referring to the average speed of a bus in Paris. I am unimpressed.

Besides, in the first month they are going to have at least one old lady fall on the exit rollers with her gigantic suitcase and 40 other people will be force-fed into the melee to create a giant writhing heap.

All it will take is one idiot and his lawyer to mess it up for everyone else.

Yup, fortunally this is france. Although they already been so weak as to pay damages, (do car manufacturers pay damages when you slam into a wall at the cars maximum speed?) hopefully they will be less susceptible to frivilous lawsuits.

Just put a sign up that says you are using it at youre own risk and that the elderly, women and other idiots should just walk. Of course there should be a normal walkway to the side (if for no other reason then to allow maintenance)

My fists start to itch when I read that stupid womans remark about her mother being scared. You don't have to fucking use it. I am tired of having the world fit itself to the lowest common denominator. This is a nice idea wich could solve some basic problems in large public areas like airports. Stupid people will always be falling over. Don't let the stupid people rule our lives.

This is a neat thing. I guess they're using it or have at least tried it out at a few other places around the world.

I had read in a newspaper report some months back that authorities in Mumbai, India were planning to install this kind of 'travelator' to link two of the most important railway stations in Mumbai, Churchgate and CST. But I don't remember seeing any action on it since then.

Btw, I would like to advise the travelator operators in Paris to hand out barf bags to people travelling on these contr

Wow! After I say goodbye to the wife Jane, my boy Elroy, daughter Jane, and pat Astro on the head, I can hop on one of these babies and start another productive day at Spacely Sprockets. Ain't the future grand?

It's not really a big innovations. The French did it 103 years ago, during the 1900 exhibiton. A rolling sidewalk [gallica.bnf.fr] was running along the exhibition and was whisking visitors at about 8 km/h. It was composed of two side-by-side rolling sidewalks [gallica.bnf.fr] one going at half the speed as the other.

If you ask me, this was a much better design than the neck-breaking jallopy installed in Montparnasse Station...

They also experimented some 30 years ago with one that was shaped like an integral sign; instead of a rubber plate, there were solid plates which slide sideways at the end, effectively yielding a slower speed but without the jarring hells-on-wheels acceleration.

Yep. And I live in Paris. In the last 6 months or so, I went to Montparnasse station about 10 time, and have _never_ seen the High Speed Travelator working (always closed because they were 'fixing' it).

There have been a lot of stories in the newspaper about it. Basically, it doesn't work. A waste of money, specially considering the lack of escalators in most of Paris metro stations...

I live in Paris and tried it a while ago. It works like a charm. The acceleration and deceleration are surprisingly smooth provided you keep your feets on the ground. Then it is exactly like a normal conveyor mat. I like it and I see no drawbacks.

How about we use this idea for certain roads where Point A and Point B are 400 miles away...

Example:

Drive your car onto Interstate 95 where a rubber coated ramp picks up the car. There would be 3 lanes... Left would be fastest, if you knew that you would be on the road for a while... Middle for those that don't need to go to far (one city to another)... Right is slowest for those who would be getting off soon and transferring onto an exit conveyor where the speed would gradually reduce to normal commuting

Personally, I think more could be done with this concept. If the center, fastest "strip" was a sit down type one, wouldn't this really be nothing more than a permanently available, perpetual people bus. Think about it, moving McDonalds, talk about fast food!

As well, these conveyers could easily be constructed as subways. I can also see these being used at large exhibition

One of the main hobbies of people in Paris is sitting in sidewalk cafes watching people go by. If this invention catches on, what will happen? Will people sit in the cafes and people will go wooshing by, or will the cafe also be on the moving part?

Why don't they use something like a maglevel/chairlift. On which individual carriages are propelled (at any acceleration you like:-) down a track that doesn't have the limitation of being flat and straight.

No! I thought, uh, I thought I'd chauffeur myself this evening. Yes, that's what I thought. How difficult could it be? I'm sure the manual will indicate which lever is the velocitator and which the deceleratrix, hmm?

[sarcasim]How can this even get off the ground if future cities are designed around the Segway AKA Ginger? Ginger is the future "Human Transporter" . Ginger is "IT" !. Steve Jobs told me so! There's no place for something like this.[/sarcasim]

Seriously though, I think the *real* future is in hydrogen fuel cell vehicles (whether they be private cars or public buses) for three reasons. First, that's where all the serious R&D money is going right now. Secondly, they require no great leap of concept and will be more psychologically acceptable to the public (i.e. its just a car with a different engine as opposed to something strange and possibly "dangerous"). Third, other than adding hyrdogen pumps to existing gas stations, they requie no expesive and massive public works project because they can use the current road infrastructure. The gas station problem can be handled by a government regulation on the lines of "if you run a gas station and have more than two pumps, at least one has to be for hydrogen".

Now if they could jack up a fuel cell powerful enough for a jet engine capable of inter-city/cross-country transport, we'd be set.

There have been many attempts to solve the speed transition problem for moving sidewalks, going back to the Paris Exposition of 1900. The usual idea is to have a speed transition between two conveyor belts, and the usual problem is to avoid someone getting caught or tripped at the transition point.

The Loderway Accelerating Walkway [elevator-world.com], circa 1998, used multiple belts at different speeds. The transitions between belts involved a 5mm drop and small-diameter end rollers [elevator-world.com], instead of a transition plate. That was probably the simplest solution to the problem. Two systems were installed in Australia, field tests were claimed to be successful, but the manufacturer no longer seems to be around.

NKK [jfe-holdings.co.jp] (yes, the zipper company) and Mitsubishi have both built prototype "accelerating moving walkways", but neither system seems to have been installed more than once. NKK's system involves expansible plate-type steps that become longer in the high-speed section. The Mitsubishi [elevator-world.com] system works by turning a corner, so that a series of short wide plates transform into a series of long narrow plates. Both of these systems avoid difficult transition points, but are complicated and expensive throughout the whole length of the system. The Loderway and Paris systems have transitions, which adds risk, but the long section is just a plain belt, so the cost of long systems is manageable.

The telescopic-panel idea is reasonable, but mechanically complicated. They have to telescope slowly where they're supposed to, so there's a linkage underneath and a fair amount of mechanical complexity.

The original moving walkway at the Paris Exposition around 1900 was really an endless train of flatcars with continouous platforms on top. Transitions between cars were handled by circular sections. There were were steps (with vertical overlaps) between the slow train and the ground, and between the fas

Seems like the French aren't afraid to try techno-miracles -- I haven't seen any metro system as good -- London is close, but alot of inconsistencies. In Paris and France, they aren't afraid to try new things (and the US stilldoesn't have any high-speed trains....bunch of cowards -- look big behindtheir high-tech weapons -- but when it comes to something socially useful...forget it. It was a shame the French became the only company to provideSuper-Sonic speeds on jets -- and, of course, what did we do in the US?We banned their use in US airspace because Elmer's cow might stop producingmilk from the occasional bang. Big woop. We could have had coast-to-coastin 2-3 hours, but noooOOOOOooo.... any real R&D goes to defense wherethey don't have to worry about every soldier who breaks a nail suing them.

Americans are just so damn stupid so often....that and greedy. Grrr.

Why can't the US every take the lead in these areas --- because it's alwaysprivate development and unless the private developer can prove profit (minusreal or bogus lawsuits) before it is even tested, it falls dead on the designfloor.

I really thought the Casino bosses in Las Vegas just might pull off thehigh speed train idea to L.A. But it's been ages since I heard that ideafloat.

Everyone in the US seems to want to have the right to stop progress that can benefit large numbers of people -- like all the poltics with the "Rich"who can buy their congressmen in Menlo Park/Palo Alto and don't want BARTto go through their town -- we were promised it would circle he Bay and havebeen paying sales tax to support it since...when, 1970's? Everythingis politics and self-interest.

If you would RTFA you could see that these are about three times as fast, which presents a problem when people have to get on or off. So all the magic lies in the acceleration and deceleration zones. The rest is more or less an ordinary travelator at high speed.

after reading the article, posting, then re-reading the article, i still ask the same question: don't we already have these? I mean, its only 11km an hour, and hell, if its 3km/hour in the airport, is it worth it for the speed jump?

Ahh but that's where you are wrong. This is a new business model of getting people to their computers/internet connection faster. That way they can buy stuff from your website (i.e. amazon.com) much more often. If you can move the people 50 times faster than they can walk, you can increase your profits by a factor of 50 (well not really but it's good enough for the patent office). And, of course, if someone walks on the Amazon.com travelator to get to a computer to order off of BarnesandNoble.com, it is